1. Field of the Invention
The present invention relates to a sorting apparatus and a sorting method for sorting a desired article from a plurality of articles to be sorted, and an alignment apparatus for transporting a plurality of articles to be sorted.
2. Description of the Background Art
It is required that articles which belong to a desired category be sorted from a plurality of articles having various colors, sizes, etc. Conventionally, desired articles have been sorted based on the color, size, etc., of the articles to be sorted through the human eyesight. In recent years, sorting apparatuses have been proposed which sort desired articles using CCD (charge-coupled device) cameras (refer to, for example, JP-A-04-346877).
In the sorting apparatus according to the above-described JP-A-04-346877, the seeds are transported at intervals by a transport apparatus with a vibration generator, and the image of each of the seeds is obtained by a CCD camera. The color or size of the seed is determined based on the image of the seed obtained by the CCD camera, and the seeds determined to be rejected are sucked and extracted by an extraction device, so that the seeds are classified into accepted seeds and rejected seeds.
In the sorting apparatus according to the above-described patent document, however, the seeds are transported by the vibrations by the vibration generator in the transport apparatus, and therefore, the seed-transporting speed is low. As a result, it requires a great deal of time to sort the seeds. Moreover, since the color or size of the vibrating seeds is determined, it is difficult to accurately sort the seeds.
On the other hand, as a seed sorting apparatus for sorting seeds according to the genetic traits, an apparatus has been provided which sorts seeds by measuring the condition of the surface design of a seed and binarizing the measured result to compare this binarized image with a value of reference distribution of a seed stored in a storage in advance(refer to, for example, JP-B-3334003).
In the above-described seed sorting apparatus, however, the seeds are sorted by converting the image of the surface design of a seed into a binarized monochrome image, and therefore, it has been difficult to sort the seeds having the same surface condition with different colors.
Further, a seed sorting apparatus has been also provided which sorts the seeds according to color by a color sensor. It has been difficult, however, to accurately sort the identical seeds when some of them have non-uniformity in color. It has also been difficult to accurately sort the seeds according to color when some of them have white parts, that is, no color at their peripheries or string parts inside.